Anatomically, it is Brodmann’s area 8, together with parts of areas 6 and 9, situated in the prefrontal cortex, just rostral to the premotor cortex, in the prefrontal and frontal gyrii that projects to the caudate nucleus in the basal ganglia. Together with the superior colliculus (both of which discharge immediately prior to saccades), it is mainly responsible for the voluntary control of saccadic eye movements, and can control eye movements independently of the superior colliculus (thus, indicating that these two structures constitute complementary pathways for the control of saccades, but with some partial compensation when one of them is damaged). Of all the cortical eye fields, the FEF are unique in a number of ways. Firstly, it codes saccades in retinocentric coordinates. Secondly, via the superior colliculus, it has both direct and indirect connections with saccade generators (‘gaze centres’) in the brain stem (viz., paramedian pontine reticular formation near the midline of the pons and the rostral interstitial nucleus in the rostral part of the midbrain reticular formation that generate horizontal and vertical eye movements, respectively). Thirdly, it produces saccades in the absence of current visual information. As with the supplementary eye fields (SEF) that have a less specialized role in the control of saccades, it has connections with the dorsolateral prefrontal cortex, the main substrate for working memory, that is also assumed to a play a role in guiding eye movements. In fact, the FEF occupy a privileged position in such control due their rich set of connections with the occipital cortex, inferior temporal (IT) cortex, and parietal cortex, with the superior colliculus having indirect inputs to the FEF through the pulvinar of the thalamus and then the IT cortex (see figure below). Developmentally, there is suggestive evidence that oculomotor control by the FEF appears at about 4 to 6 months of age, but recent evidence indicates that it may be achieved at even younger ages, and so this debate about first age of appearance continues.
